Various different surgical eye treatments exist, such as photorefractive keratectomy (short: PRK) and laser assisted in-situ keratomileusis (short: LASIK) for improving visual acuity of the eye by correction of myopia, hypermetropia, astigmatism or the like, or cataract surgery for implanting an intraocular lens.
For the individual preparing and planning of such surgical eye treatments, determination of biometric properties of the eye is required by identifying the geometrical characteristics of the eye to be treated.
Existing systems for determining biometric properties of an eye employ a measuring light beam for providing data, which represent distances between surfaces on or in the eye, such as surfaces of the cornea, the lens and the retina of the eye. So far, the data provided by such existing systems merely represent the distances along a single beam path of the measuring light beam, i.e. existing systems determine biometric properties of the eye on basis of only a single scan.
However, because of the eye's geometry, the measured distances between the surfaces on or in the eye depend on the specific optical beam path, along which the measuring light beam propagates through the eye. These beam path dependent distances result in uncertainties of the biometric properties determined by the existing systems. Furthermore, by the existing systems for determining biometric properties of an eye it cannot be extracted, along which specific beam path the measuring light beam propagated during the single scan.
Therefore, it is desirable reduce or even avoid uncertainties in determined biometric properties of an eye.